#!/bin/sh -e
#
#    network: calculate the network up/down rates
#
#    Copyright (C) 2008 Canonical Ltd.
#    Copyright (C) 2011 Dustin Kirkland
#
#    Authors: Dustin Kirkland <kirkland@byobu.co>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, version 3 of the License.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.

__network_detail() {
	get_network_interface; local interface="$_RET"
	LC_ALL=C /sbin/ifconfig "$interface" | $BYOBU_SED 's/\s*$//'
}

__network() {
	get_network_interface; local interface="$_RET"
	local x1=0 x2=0 tx1=0 i= t= unit= symbol= cache= rate=
	status_freq network
	t="$_RET"
	# By default, we won't bug the user with the display of network traffic
	# below NETWORK_THRESHOLD in kbps; override in $BYOBU_CONFIG_DIR/status
	[ -n "$NETWORK_THRESHOLD" ] || NETWORK_THRESHOLD=20
	for i in up down; do
		unit="kb"
		case $i in
			up) symbol="$ICON_UP" ;;
			down) symbol="$ICON_DN" ;;
		esac
		cache="$BYOBU_RUN_DIR/cache.$BYOBU_BACKEND/network.$i"
		[ -r "$cache" ] && read x1 < "$cache" || tx1=0
		local iface rbytes rpackets rerrs rdrop rfifo rframe rcompressed rmulticast tbytes tpackets terrs tdrop tfifo tcolls tcarrier tcompressed
		while read iface rbytes rpackets rerrs rdrop rfifo rframe rcompressed rmulticast tbytes tpackets terrs tdrop tfifo tcolls tcarrier tcompressed; do
			case "$iface" in
				${interface}:)
					[ "$i" = "up" ] && x2=${tbytes} || x2=${rbytes}
					break;
				;;
				${interface}:*)
					# Interface and tbytes got munged together
					[ "$i" = "up" ] && x2=${rmulticast##*:} || x2=${iface##*:}
					break;
				;;
			esac
		done < /proc/net/dev
		printf "%s" "$x2" > "$cache"
		rate=$((8*($x2 - $x1) / $t / 1024))  # in kbps
		[ "$rate" -lt 0 ] && rate=0
		if [ $rate -gt $NETWORK_THRESHOLD ]; then
			case "$NETWORK_UNITS" in
				bytes)
					rate=$(($rate/8))
					if [ "$rate" -gt 1048576 ]; then
						fpdiv "$rate" 1048576 1
						rate=${_RET}
						unit="GB/s"
					elif [ "$rate" -gt 1024 ]; then
						fpdiv "$rate" 1024 1
						rate=${_RET}
						unit="MB/s"
					else
						unit="kB/s"
					fi
				;;
				*)
					# Default to bps
					# Why 1000 and not 1024?  http://en.wikipedia.org/wiki/Data_rate_units
					if [ "$rate" -gt 1000000 ]; then
						fpdiv "$rate" 1000000 1
						rate=${_RET}
						unit="Gb"
					elif [ "$rate" -gt 1000 ]; then
						fpdiv "$rate" 1000 1
						rate=${_RET}
						unit="Mb"
					fi
				;;
			esac
			[ -n "$rate" ] || continue
			color b m w; printf "%s%s" "$symbol" "$rate"; color -; color m w; printf "%s" "$unit"; color --
		else
			rm -f "$BYOBU_RUN_DIR/status.$BYOBU_BACKEND/network"*
		fi
	done
}

# vi: syntax=sh ts=4 noexpandtab
